Question

A) (7-x)(7+x)+(x+3)^3 если x =-3,5 b) (2a-b)^2-(2a+b)^2 если а = 1.3/7, b = 0,07 Если кому-то непонятно, то вот это ^3 обозначает степень числа.

Answer 1

А.)(7-(-3.5))(7+(-3.5))+(-3.5+3)³
1.)7-(-3.5)=7+3.5=10.5
2.)7+(-3.5)=7-3.5=3.5
10.6*3.5+(-3.5+3)³
37.1+(-0.5)
37.1-0.5=36.6
36.6³=49027,896

Answer 2

Sure, let's solve the expressions step-by-step:

a) We have the expression (7-x)(7+x) + (x+3)^3, and we are given the value x = -3.5. Let's substitute the value of x into the expression and then calculate it:

Substitute x = -3.5 into (7-x)(7+x): (7 - (-3.5))(7 + (-3.5)) = (7 + 3.5)(7 - 3.5) = 10.5 * 3.5 = 36.75

Substitute x = -3.5 into (x+3)^3: (-3.5 + 3)^3 = (-0.5)^3 = -0.125

Now, add the results of the two calculations: (7-x)(7+x) + (x+3)^3 = 36.75 + (-0.125) = 36.625

So, when x = -3.5, the value of the expression is approximately 36.625.

b) We have the expression (2a-b)^2 - (2a+b)^2, and we are given the values a = 1.3/7 and b = 0.07. Let's substitute these values into the expression and then calculate it:

Substitute a = 1.3/7 and b = 0.07 into (2a-b)^2: (2 * (1.3/7) - 0.07)^2 = (2.6/7 - 0.07)^2 = (0.37142857142857144 - 0.07)^2 = 0.30142857142857144^2 ≈ 0.09085714285714287

Substitute a = 1.3/7 and b = 0.07 into (2a+b)^2: (2 * (1.3/7) + 0.07)^2 = (2.6/7 + 0.07)^2 = (0.37142857142857144 + 0.07)^2 = 0.44142857142857146^2 ≈ 0.19485714285714284

Now, subtract the result of the second calculation from the first one: (2a-b)^2 - (2a+b)^2 = 0.09085714285714287 - 0.19485714285714284 ≈ -0.104

So, when a = 1.3/7 and b = 0.07, the value of the expression is approximately -0.104.